Talk about heroes who always go with the law do so much good but lets take a look at other types of heroes one of them is Anti-Hero, anti-heroes will protect the world even if it means breaking the law they don't care as long as the city is safe and also they don't care if they are a mercenary like half hero half mercenary that's an anti-hero.
Number 5 : Batman ([The Dark Knight Rises](movie:39011))
Why would he be on this list well for starters he doesn't care about interrogating he'd do whatever it takes to get information out of others Batman fears nothing and he can do anything even kill someone to stop them from getting in his way.
Number 4 : Arrow/Green Arrow ([Arrow](series:720988))
Arrow is good guy he's a hero just an anti-hero he only wants what's best for Starling City he would sacrifice himself as long as Starling City is safe his interrogating skills is way more dangerous than Batman's he doesn't care if the guy dies.
Number 3 : Gambit (X-Men Origins Wolverine)
Now we get down to the real Anti-Heroes Gambit is hero and a non hero he's a hero by day criminal by night (if you know what I mean) Gambit he has a lot of unique abilities which he uses for his own personal gain he shows no mercy to anyone.
Number 2 : Rorschach (Watchmen)
Rorschach is wanted criminal and also detective only he doesn't like siding with the police he is the most bravest in his gang to torture someone no remorse.
Number 1 : [Deadpool](movie:38663) (Deadpool)
It all comes down to Deadpool you can try and kill him but he'll get back on his feet with his healing factor and weapons expert he is a mercenary for hire and a hero who just loves to kill people.